In a virtualized data center, different virtual networks can be hosted on the same physical network. For example, a physical network can include more than one virtual network (e.g., a physical network can be treated as a multiple overlay network). Each virtual network can include one or more virtual machines (e.g., hosts) with unique internet protocol (IP) addresses. Virtual machines with conflicting internet protocol (IP) addresses may be hosted on the virtual networks coupled to the same physical switch. For example, one or more virtual machines on a first virtual network can include the same IP address as one or more virtual machines on a second virtual network. Furthermore, a virtual network can be implemented on multiple physical networks. For example, one or more virtual machines in a virtual network can be coupled to a particular router (e.g., a particular physical router) and one or virtual machines in the virtual network can be coupled to a different router (e.g., a different physical router). Therefore, a tunneling protocol can be implemented to forward a data packet between physical routers. However, conventional virtualized network systems do not adequately provide isolation between virtual networks when implementing a tunneling protocol.